Global shale

June 17, 2014

Czarek Sokolowski/Associated Press

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Samples of shale rocks and maps of Poland's shale gas deposits and exploration licenses are displayed at the State Geological Institute in Warsaw, Poland on Wednesday, March 21, 2012 during the presentation of the institute's report, which estimated the nation's recoverable shale gas reserves at between 346 and 768 billion cubic meters, below expectations. Poland is hoping that unconventional gas will help to break its dependence on Russian gas imports.

Czarek Sokolowski/Associated Press

8of23

Samples of shale rocks and maps of Poland's shale gas deposits and exploration licenses are displayed at the State Geological Institute in Warsaw, Poland on Wednesday, March 21, 2012 during the presentation of the institute's report, which estimated the nation's recoverable shale gas reserves at between 346 and 768 billion cubic meters, below expectations. Poland is hoping that unconventional gas will help to break its dependence on Russian gas imports.